


My Boy

by ReaThompson



Category: Shingeki no Kyojin | Attack on Titan
Genre: Child Levi (Shingeki no Kyojin), F/M, Female Eren Yeager, Fluff, Gender or Sex Swap, Genderbending, Happy Ending, Implied Eren Yeager/Erwin Smith, Love
Language: English
Status: In-Progress
Published: 2015-07-30
Updated: 2016-08-11
Packaged: 2018-04-12 02:34:55
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 3,129
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/4462082
Author URL: https://archiveofourown.org/users/ReaThompson/pseuds/ReaThompson
Summary: <blockquote class="userstuff">
              <p>Due to the accidental spilling of a lab solution on him, Levi turns into a 5 year old boy. Eren decides to take care of him.</p><p> </p><p>NOTE: This fanfiction has no connection with any of the OVAs or official spinoffs of Attack on Titan l Shingeki no Kyojin.</p>
            </blockquote>





	1. Thin and Frail

It was evening when Hange sent a soldier to inform Eren to meet her in one of the empty rooms in the castle. Thinking that it must be an emergency, Eren quickly put down her duster and left. When she opened the door, the first thing that caught her eye was a frail, thin black haired boy standing at the corner of the room.

"Who's this?"

She looked at Hange for an answer. Hange smiled at her gingerly, not saying a single word. Eren turned her head over to the black haired boy. He looked like a five year old child dressed in dirty, ragged clothes. What Eren couldn't comprehend was that the castle was very far away from the town. It wasn't possible for a child to wander that far off into the woods. The black haired boy stood there as he studied the two women. _He looks like..._ Eren stood at the doorway, shocked as she looked at the boy's familiar face. 

"Captain?!"

She immediately dashed to the little boy. Her face paled as her mind raced with possible reasons to explain what had happened to him. 

"It was an accident. I wanted to try this experiment out on you actually, but he refused, saying that it was too dangerous. He was going to leave, when the solution got spilled on him, and he..." 

Eren's eyes started to tear up as she listened to Hange's explanation. 

"Now he's a five year old, both physically and mentally. I tried speaking to him, but he hasn't said a word since morning. He doesn't seem to have any recollection of us, or of his past memories." 

Hange's face darkened. 

"I'm not even sure if I can find the antidote for him. When he transformed, the pain made him crash into my equipment. The list of ingredients I used to make the solution was destroyed." 

_Captain...!_

Eren kneeled in front of him, and grabbed his arms gently. _No... You're humanity's hope. We need you. Humanity can't win without you!_ Her arms started shaking as she clung onto his shirt. Tears started rolling down her cheeks. Panic flooded into her heart. 

"Why are you crying?"

Eren felt something warm pat her head. She looked up. The child was patting her head softly, "Did someone bully you?" Her eyes widened. It was the first time he spoke throughout the entire day. She quickly rubbed her eyes, "N... No. No one bullied me." The boy smiled, "Okay. Tell me if there is." In an instant, all her insecurities melted away. _The captain everyone loved was still here_. Eren rubbed the last of her tears away, the panic she felt earlier was gone. 

"Eren. I might not be able to find an antidote, but..."

Eren turned to look at Hange, anxious to know what she was going to say next.

“The good news is, Levi will be able to grow up like a normal child.” 

“Huh?”

Eren slumped onto the floor. She doesn’t know what she should be feeling. Should she feel relief? Or should she feel devastated? Humanity’s strongest has become a child, both mentally and physically. The good news was that even without an antidote, he could still grow up and become a healthy man. However, it would take years before he could finally become the disciplined, talented man that he was.

Slowly, she reached out for his hand. The boy jolted, but didn’t pull his hand back.

“I’ll take care of you.”

Eren carried the boy in her arms. Her heart ached as she felt the thin bones of the boy—

Was the young captain mistreated as a child?

Hange watched as Eren left the room with him. It was Hange’s own fault that things had ended up that way. She felt worse when she saw how devastated Eren was. It was like all hope had been drawn out of her. She could feel the panic, the despair, and the pain that was written all over her face.

 

* * *

 

Eren sat on her chair quietly, listening as the boy sipped tea from his cup.

“What’s your name?”

Eren jolted from her seat. She turned her head, and met the eyes of the child. His pair of silver eyes stared at her curiously.

“My name is Eren Jaeger.”

He placed his cup on the table. He smiled happily at her.

“I’m Levi.”

She nodded. Levi continued drinking his tea, sipping it sweetly like nothing had happened. Eren didn’t know what to do, or what to say. He may be a child now, but deep down he is humanity’s strongest, Captain Levi Ackerman. She couldn’t help but not know what to talk about. She looked out the window. It is night now, and the moon is up.

_What will tomorrow bring us…?_

 


	2. The next day

He is sleeping now.

Eren watched as the young boy’s chest rose and fall, blissfully unaware of his surroundings. The two are now resting in one of the rooms in the abandoned wing of the castle. At first Eren wanted to bring him back to his own room, but realized that she shouldn’t.

_What if someone comes into the room and finds a mini captain lying on the bed?_

She rubbed her temples. It was going to be daybreak. She just can’t believe that the man she admired for so long… is a child now. Hange is intelligent, but it will take a matter of time before she discovers the cure. How will they seal this from the others? Won’t people question the disappearance of the renown Captain? Rumors will start flooding around the camps, and sooner or later havoc will arise.

Panic. Fear. Anger.

It will not only be felt by the Survey Corps but by all. Captain Levi is Humanity’s Strongest. How can humanity lose its strongest soldier? The feeling of fear started choking her. The warm feeling that the boy had given her previously was now gone. She closed her eyes, trying to cleanse the paranoia from her mind.

What if Hange can’t find a cure?

What if it was all lies?

What if there were more side effects from the potion than just a loss of memory and the shrinkage of his body?

Eren clenched her fists as her eyes shot open.

_I must have faith..._

* * *

 When the boy woke up, he was greeted by a smiling, young brunette. Her green orbs shone at him warmly, invitingly. He doesn’t know her. All he remembers was that she was the one who took him away from a frantic glasses-wearing woman. She passed him a piece of bread.

“Captain, come eat some bread.”

Her voice gave him a very comfortable feeling, like a bath of warm water. He doesn’t recall himself having one, but maybe this is what it feels like.

“Captain, come drink a glass of milk. Do you want more bread?”

He shook his head. She still put it in his hands anyway. A soft smile graced her face as she watched him drink.

“Aren’t you going to eat?”

The young woman stared at him, dumbfounded. A look of surprise mixed with joy crossed her face. She shook her head at him. He pointed at the tray on the table nearby. There was three pieces of bread on the plate, as well as two cups: one that was filled with milk that he had finished, and the other still filled to the brim with nothing but water.

“I don’t have the appetite to eat now.”

The boy doesn’t seem to understand. Was she in trouble?

“Why?”

_Because you’re nothing but a child, Captain._

Eren stood up, her eyes now glowing sadly. The boy had woken up early, like she had expected him to.

“Go back to sleep, Captain. I need to go out and do something. I’ll be back soon.”

The boy nodded. She closed the door behind her.

* * *

Even before she reached the dining hall she heard Aoruo’s loud voice. As she expected, the moment she walked in, he screamed at her.

“Who the hell do you think you are?! Walking in so late! Don’t you have any respect for your seniors?!”

Erd sighed, while Gunter shrugged. Petra tried to calm Auruo down.

“Auruo! Calm down. Maybe something happened, that’s wh-“

“Stop protecting the newbie! Who cares if she had something important to do?! We’re her seniors, she should come here far earlier before us!”

Eren sat next to Erd. The trio Erd, Gunther and Eren end up watching the two quarrel. What’s there to do anyway? The Captain isn’t here yet to give them orders.

“Hey… What’s taking Captain so long?” Erd asks, puzzled by the lateness of their Captain.

“I don’t know. Is he supposed to be in a meeting?” Gunter replied him, trying to remember whether the Captain did inform him that he was supposed to be late or absent for the morning meeting.

“How should I know? He didn’t tell me anything!” Auruo rolled his eyes, angry that his friends seem to look so carefree about the sudden out-of-character behavior of their Captain, who was never late.

“He didn’t tell me anything either,” Petra’s face crumples up with worry.

The group looks at Eren. She shrugged, “I don’t know anything either.”

The group began to discuss the reasons why he was so late. Did he oversleep? Gunter shook his head at Erd’s question. He had went to his room earlier, but he wasn’t there. Maybe he’s in a meeting. Auruo frowned at Petra. How can the Captain just leave without giving a proper notice to them that he’s in a meeting? It was not in his character to do so. Maybe it was an emergency? Auruo got pissed at her, which resulted in the two screaming at each other again. In the end the group decided to stay in the hall for another hour for the Captain to show up.

_No matter how long you guys wait here…_

_He’s not going to come._

Eren sat in her seat patiently, until she realized that there was a little boy left in the abandoned wing of the castle. As minutes passed by, she grew irritated. She started moving around in her seat, restless.

“Hey newbie. What’s wrong with you?”

Auruo glared at Eren.

“Since you came late, you should have the decency to wait for Captain Levi. Don’t you ever think of leaving.”

Eren glared back at him. She snickered, “So why don’t you leave first?”

Auruo grabbed her shirt, and flung a punch at her face. Erd grabbed Auruo’s fist in time. He slammed him into the cold wall.

“Auruo, you like picking fights with Eren, don’t you?”

Erd sighed.

“And don’t use the ‘she was being disrespectful to me’ card. It’s not going work every time you know.”

Auruo rolled his eyes as Erd let go of his wrist. He cussed, then sat back down quietly, angrily.

“Hmm..? You guys done with the fight already? I was hoping for more.”

Everybody turned their heads to the door. Hange was standing there, her face plastered with a huge smile.

“Your Captain’s been stuck in a meeting with the ‘pigs’. He won’t be coming back in a few weeks’ time.”

The group nodded.

“Is there anything else that he wanted us to do?” Petra asked.

“Yeah. Make sure the place is clean as fuck when he gets back.”

Hange laughs as she leaves the hall. One by one, they left too. Eren was the last to leave. She didn’t want anyone to follow her.

After all, who wants to feel as helpless as her?

No one. 

 

 


	3. Just You

Eren ran down the hallway as fast as she could manage. She started out slow at first, but broke out into a run the moment she realized that it was already late afternoon.  The moment she stepped into the room, she panicked. The bed was empty. The boy was nowhere to be seen.

“Captain?!”

She sat the bag she hid Levi’s food in on the wooden chair nearby. _Where could he be?_ She chewed her lower lip, forcing herself to come up with ideas as to where he might be. _Where would a kid go when they’re in a foreign place?_ Eren frowned, closing her eyes. _Wouldn’t they stay in the room? Since it’s a strange, unknown place, wouldn’t they want to be somewhere safe? Like for example, the room?_ Eren sighed. _Somewhere safe huh…_ _When feeling insecured, children will seek out reassurance from a room, an object, or a person._ She knows. She chuckled darkly, humoured by her own past. Whenever she felt insecured, or unsafe, she would always go look for— Her eyes snapped open.

_Me._

_He’s looking for me._

Eren picked up the bag up from the chair, and slowly walked back into the corridor. She headed towards the opposite direction of where she came from, praying that she would find him soon. She opened the doors of each room she passed by, only to be met with nothing but disappointment each time.

“Captain…?”

She whispered as she opened the last door. It was empty. Her heart was getting heavier and heavier with each passing second. It is evening now. She still hasn’t found him. Worry filled her heart. She has searched every floor and every room in the wing, but he is still nowhere to be seen.

_What do I do now?_

She clenched the bag that she was carrying, holding it close to her chest. _He must be hungry_. _A piece of bread isn’t enough for a growing child…_ She hadn’t eaten anything at all today, but that doesn’t matter. What matters the most is her captain. Ever since she got transferred under his watch, he’s been the one looking after her. He watches over her, making sure that she doesn’t injure anyone and herself. Whenever she shifted, he would be close by. He was the one who would carefully extract her out of her titan body and lay her down gently.

Now, at his lowest, she can’t even take care of him.

She sat there, dazed, buried in nothing but guilt. Why can’t she take good care of him? Yes, it was Captain’s job to watch over her, but he was good at it. He was kind, and did not treat her as a burden. Whenever the shifting failed, he wouldn’t lecture her. He would talk to her in that calm voice of his, making her feel that everything would be okay. When she was down, feeling like a failure, he would try to lift her spirits. His attempts at jokes were terrible though.

She laughed at her last thought. His jokes were always about shit, and is as terrible as shit itself. She remembered sitting at the dining hall upset and didn’t notice when he came in. He asked her, “What, you constipated?” It made her laugh. She didn’t know why though. No matter how many times he said that she would still laugh at that line despite how upset she would be at the time. Captain would watch her laugh, and she sometimes wonder whether she imagined the small smile on his face whenever she did.

Eren stood up from the floor. She can’t let her guilt overtake her now. She has to find him. She has to make him feel safe, just like how he always made her feel. Thinking that he might have gone back to his room, she headed back there.

She opened the room door nervously.

“Captain!”

The black haired boy was sitting on the bed, playing with a crunched up paper ball. He turned to look at her, his blue eyes gleaming with curiosity. The curious look on his face got replaced by worry. She looked terrible.

“Are you okay Eren?”

She didn’t even reply him. She went straight to him, and hugged him tight.

“I was so worried, I was so scared that I lost you, I was just so—”

She hugged him close to her chest, feeling that if she didn’t, he’d disappear on her again. She held him in her arms for a long time. The feeling of panic, fear, and guilt that she felt earlier were all fading away. When she felt that she calmed down, she let him go.

Levi looked straight into her green eyes. The two maintained eye contact, until he broke it. He lowered his head, “I went to look for you when you didn’t come back.”

“I’m sorry.”

Levi’s head shot up. From the expression on his face, he wasn’t expecting an apology from her. Eren took out two boiled potatoes from her bag, as well as a small loaf of bread. She smiled when he began eating one of the potatoes. His pale blue eyes still looked puzzled as he ate.

“I’m sorry because I didn’t look after you like I was supposed to.”

Levi shook his head. He still looked like he did not understand what she meant.

“Captain, you took care of me in the past.”

“I don’t remember.”

A small, sad smile graced Levi’s face. “Why do you keep calling me Captain?”

Eren wanted to tell him. She wanted to tell him who he was. _I call you Captain because you are my captain. You are Captain Levi. Humanity’s strongest. The unbeatable man._

“I call you Captain because you’re my captain.” Eren said plainly. The line could be interpreted both ways. She smiled at him.

“Don’t call me Captain.”

Eren’s smile faded.

“Call me Levi, Eren.”

The child looked up at her, with nothing but hope in his eyes. He was confused.

“What is so hard about calling me by my name?”

She couldn’t answer him. Captain had lost his memories after all. It wouldn’t hurt calling him by his name… would it? She remembered the many nights where she wanted to feel the sound of his name rolling on her tongue without saying ‘captain’ before it. To know the real Captain, not the façade that he puts on for everyone. He’s strong and powerful, but she knows that he’s broken.

She remembers how much she wanted to be there for him.

There were times when she caught him staring into nothingness, a blank expression on his face. If he knew she was there, he didn’t say a word. He’d just continue, a long comfortable silence between them as he stayed in that state of mind.

_What are you thinking about, Captain?_

She closed her eyes, the image of him floating into her mind. It pained her to see him that way. To hear the broken pieces of his heart fall onto the cold floor.

_Let me be there for you._

“Nothing, Levi. I’m just not used to calling you by your name, that’s all.”

Eren smiled at the boy.

 _Let me be there_.

 

**Notes for the Chapter:**

> Don't hesitate in rushing me. I'm a lazy prick so go ahead. I won't mind, as long as you don't swear. Hahah thanks for reading!


End file.
